An SiC formed body (CVD-SiC formed body) that is obtained by depositing SiC on the surface of a substrate using a chemical vapor deposition (CVD) method, and removing the substrate, has high density and high purity as compared with an SiC formed body produced using a sintering method, and exhibits excellent corrosion resistance, heat resistance, and strength. Therefore, it has been proposed to use the CVD-SiC formed body as a heater used for semiconductor production equipment, a dummy wafer, a susceptor, and a reactor core tube used for an etcher and a CVD device, and the like (see Patent Document 1 (JP-A-2006-16662), for example).
However, when using the CVD-SiC formed body as a heater for semiconductor production equipment, the CVD-SiC formed body is required to have a low resistivity almost equal to that of SiC produced using the sintering method in addition to the above properties. When using the CVD-SiC formed body as a dummy wafer, the CVD-SiC formed body is required to have low light transmittance. A CVD-SiC formed body having properties sufficient for use as a substrate used for semiconductor production has not been obtained.
In view of the above situation, the applicant of the present application proposed a CVD-SiC formed body that is obtained by feeding a feed gas in the presence of nitrogen gas, and has low resistivity and low light transmittance (see Patent Document 2 (JP-A-2002-47066)).